Molded articles and methods of making same



May 12, 1964 J. P. GITS MOLDED ARTICLES AND METHODS OF MAKING SAME Filed Aug. 18. 1961 2 Sheets- Sheet 1 76 77' m2 INVENTOR. Jl/LEJ P. 6/75 Arr K y 1964 J. P. GITS MOLDED ARTICLES AND METHODS OF MAKING SAME 2 Sheets-Sheet 2 Filed Aug. 18. 1961 INVEN TOR. JULESR 6/ 7':

United States Patent ice 3,132,649 MOLDED ARTECLES AND METHODS OF MAKING SAME Jules P. Gits, 1003 Lat'nrop Ave., River Forest, 111. Filed Aug. 18, 1961, Ser. No. 132,399 9 Claims, ((11. 129-24) This invention relates to improvements in molded articles and methods of making same. More particularly, this invention relates to improvements in loose-leaf binders and methods of making same.

It is, therefore, an object of the present invention to provide an improved loose-leaf binder and an improved method of making such a loose-leaf binder.

A loose-leaf binder customarily includes a large number of parts, as for example, an elongated metal support, a number of split rings of metal that are spaced along the length of that metal support, levers that can be operated to open those split rings, covers, and a backing. Such a loose-leaf binder is, of necessity, expensive because of the cost of making and of assembling such a large number of parts; and it would be desirable to provide a looseleaf binder that could be made from a smaller number of parts. The present invention provides such a looseleaf binder; and it is, therefore, an object of the present invention to provide a loose-leaf binder which can be made from a small number of parts.

The loose-leaf binder provided by the present invention includes a unitary member that constitutes the backing, the front cover, and the back cover of that loose-leaf binder. That loose-leaf binder also includes a bendable plate which has arcuate, J-shaped projections that constitute halves of openable rings; and that bendable plate and those J-shaped projections constitute a second unitary member. In addition, the loose-leaf binder utilizes two metal levers that can be used to force the bendable plate to move into a position where it will move the free ends of the J-shaped projections apart. This means that the loose-leaf binder provided by the present invention can be made from just four parts; and such a loose-leaf binder is simpler and less expensive than are present-day looseleaf binders. It is, therefore, an object of the present invention to provide a loose-leaf binder which can be made from just four parts.

The backing for the loose-leaf binder provided by the present invention has two elongated, concave recesses at the sides thereof, and those recesses accommodate elongated, cylindrical ribs at the sides of the bendable plate of that binder. The unstressed distance between those elongated, concave recesses of the backing is less than the unstressed distance between the outer faces of the elongated cylindrical rib-s on the bendable plate. As a result, whenever those elongated cylindrical ribs on the bendable plate are disposed within those elongated, concave recesses in the backing, that backing will apply compressive forces to that bendable plate. Those compressive forces will urge that bendable plate to assume either a closed-ring position or an open-ring position; and hence whenever the J-shaped projections on that bendable plate are being moved toward open-ring position, those compressive forces will urge those projections to move all the way to that position. Similarly when the J-shaped projections on that bendable plate are being moved toward closed ring position, those compressive forces will urge those projections to move all the way to that position. As a result, when pages or leaves are to be inserted into the loose-leaf binder, full and free access to the J-shaped projections will be assured; and when pages or leaves are not to be removed from the loose-leaf binder, the J- shaped projections will positively preclude such removal. It is, therefore, an object of the present invention to provide a loose-leaf binder with a backing that has elongated,

3,132,649. Patented May 12., 1964 arcuate recesses at the sides thereof which have an un stressed spacing that is less than the distance between the outer edges of the elongated, cylindrical ribs on the bendable plate of that binder whenever that plate is in its unstressed condition.

Other and further objects and advantages of the present invention should become apparent from an examination of the drawing and accompanying description.

In the drawing and accompanying description, a preferred embodiment of the present invention is shown and described but it is to be understood that the drawing and accompanying description are for the purpose of illustration only and do not limit the invention and that the invention will be defined by the appended claims.

In the drawing, FIG. 1 is a fragnentary end view of one embodiment of loose-leaf binder that is made in accordance with the principles and teachings of the present invention, and it shows that binder in open-ring position,

FIG. 2 is a view that is similar to the view in FIG. 1 but it shows the loose-leaf binder in closed-ring position,

FIG. 3 is a broken plan view of the patrix of the mold which is used in forming the bendable plate of the looseleaf binder of FIG. 1,

FIG. 4 is a sectional view through the patrix and matrix of the mold used to form the bendable plate of the loose-leaf binder of FIG. 1,

FIG. 5 is another sectional view through the patrix and matrix of the mold used to form the bendable plate of the loose-leaf binder of FIG. 1,

FIG. 6 is a sectional view through the patrix and matrix of the mold which is used to form the unitary member which constitutes the backing and the front and rear covers of the loose-leaf binder of FIG. 1,

FIG. 7 is a perspective view of part of the bendable plate used in the loose-leaf binder of FIG. 1, and

FIG. 8 is a longitudinal section through part of the loose-leaf binder of FIG. 1.

Referring to the drawing in detail, the numeral 20 denotes the front cover of one embodiment of loose-leaf binder that is made in accordance with the principles and teachings of the present invention. The numeral 22 denotes the rear cover of that loose-leaf binder, and the numeral 24 denotes the elongated backing of that looseleaf binder. A portion 26 of reduced thickness is provided intermediate the adjacent edges of the front cover 20 and of the backing 24; and that portion interconnects that front cover and that backing while permitting ready rotation of that front cover relative to that backing. A portion 28 of reduced thickness is provided intermediate the adjacent edges of the back cover 22 and of the backing 24; and that portion interconnects that back cover and that backing while permitting ready rotation of that back cover relative to that backing. The backing 24 has an elongated, concave recess 30 adjacent the portion 26 of reduced thickness, and it has an elongated, concave recess 32 adjacent the portion 28 of reduced thickness. Two posts 34 extend upwardly from the backing 24, and those posts are disposed adjacent the opposite ends of that backing. Each of those posts has an enlarged head 36, and each of those posts has a recess 38 in the upper end thereof which extends downwardly through the enlarged head 36. The front cover 20, the back cover 22, the backing 24, the reduced thickness portion 26, the re duced thickness portion 2%, and the posts 34 with their enlarged heads 36 and their recesses 33 are formed as a unitary member.

The numeral 49 denotes an L-shaped lever which will preferably be made of metal; and that lever has a horizontal arm which is longer than the vertical arm thereof. An opening 42 is formed in the horizontal arm of the lever 40, and that opening has a diameter which is smaller than the diameter of the enlarged head 36 on either of 3 the posts 34. However, that opening can be telescoped over the enlarged head 36 of either of the posts 34, because the recesses 38 in the posts 34 make it possible to locally distort the enlarged heads 36 of those posts sufiiciently to force the opening 42 down over either of those enlarged heads. Two L-shaped levers 40 are provided; and one of these levers is located adjacent one end of the elongated backing 24, while the other of those levers is located adjacent the opposite end of that backing.

The numeral 44 generally denotes an elongated bendable plate; and that plate will be substantially as long as the elongated backing 24. That plate has an elongated portion 46 of reduced thickness, as shown particularly by FIG. 7. Outwardly and upwardly inclined surfaces 48 are contiguous with the portion 46 of reduced thickness; and those portions extend to the upper face of the bendable plate 44. Those inclined surfaces coact with the portion 46 of reduced thickness to define an elongated recess in the upper face of the bendable plate 44 which is frusto-triangular in cross section. Surfaces 50 are contiguous with and incline outwardly and downwardly from the lower face of the portion 46 of reduced thickness; and those surfaces coact with that por tion to define an elongated recess in the lower face of the bendable plate 44 which is frusto-triangular in cross section. An elongated, generally cylindrical rib 52 is provided at the left-hand edge of the bendable plate 44, and the exposed surfaces of that rib define three quadrants. An elongated, generally cylindrical rib 54 is provided at the right-hand edge of the bendable plate 44, and the exposed surfaces of that rib define three quadrants. The radii of the elongated, generally cylindrical ribs 52 and 54 are similar to the radii of the elongated concave recesses 30 and 32 in the backing 24. However, the unstressed spacing between the outer faces of the elongated, generally cylindrical ribs 52 and 54 is greater than the unstressed spacing between the confronting faces of the elongated concave recesses 30 and 32 in the backing 24.

Two circular openings 56 are provided in the bendable plate 44; and those openings are adjacent the opposite ends of that bendable plate, and they extend through the portion 46 of reduced cross section and through the inclined surfaces 48 and 50. The numeral 58 denotes arcuate, J-shaped projections which extend upwardly from the inner face of the elongated, generally cylindrical rib 52 on the bendable plate 44. The numeral 60 denotes arcuate J-shaped projections which extend upwardly from the inner face of the elongated, generally cylindrical rib 54. The upper ends of the projections 58 have notches 62 therein; and the upper ends of the projections 60 have extensions 64 thereon. The notches 62 and the extensions 64 are generally V-shaped in plan, and they are complementary. Openings 66 are provided in the bendable plate 44 adjacent each pair of projections 58 and 60. A number of J-shaped projections 58 and 60 and a number of openings 66 are provided in the bendable plate 44; and each pair of projections 58 and 60 constitutes an openable ring. The bendable plate 44, the elongated generally cylindrical ribs 52 and 54, and the J-shaped projections 58 and 60 will preferably be formed as one unitary member.

The openings 56 in the bendable plate 44 have diameters which are smaller than the unstressed diameters of the enlarged heads 36 on the posts 34. However, those heads can be locally distorted to enable them to telescope through the openings 56 in the bendable plate 44; but once those enlarged heads have been telescoped through the openings 56, those heads will restore themselves and thereby prevent accidental separation of the bendable plate 44 from the unitary member which includes the front and back covers 20 and 22, the backing 24, the portions 26 and 28 of reduced thickness, and the posts 34.

In assembling the loose-leaf binder provided by the present invention, it is only necessary to telescope the openings 42 in the L-shaped levers 40 over the enlarged heads 36 on the posts 34, to telescope the openings 56 in the bendable plate 44 over those enlarged heads, and then to spread the concave recesses 30 and 32 of the backing 24 apart sufliciently to snap the cylindrical ribs 52 and 54 on that plate into those concave recesses. In this simple, quick and inexpensive way, the four components of the loose-leaf binder provided by the present invention can be assembled.

The elongated, concave recesses 30 and 32 must be spread apart to enable the elongated, generally cylindrical ribs 52 and 54 to be moved into position within those elongated, concave recesses; and the backing 24 will still be stressed after those elongated, concave recesses are permitted to move toward each other and to press against the elongated, generally cylindrical ribs 52 and 54. As a result, the backing 24 will apply laterally-directed compressive forces to the bendable plate 44; and those forces will urge that plate toward the open-ring position shown in FIG. 1 or toward the closed-ring position shown in FIG. 2. To cause the bendable plate 44 to shift from the open-ring position of FIG. 1 to the closedring position of FIG. 2, it is only necessary to urge the J-shaped projections 58 and 60 toward each other or to apply downward forces to the bendable plate in the region of the portion 46 of reduced thickness. To shift the bendable plate 44 from the closed-ring position of FIG. 2 to the open-ring position of FIG. 1, it is only necessary to press outwardly upon the vertical arms of the L- shaped levers 4i); and thereupon the horizontal arms of those levers will engage the backing 24 and rotate so the inner ends thereof will move upwardly and apply upward forces to the bendable plate 44. Those upward forces will cause the portion 46 of reduced thickness to shift upwardly through its dead-center position and cause the bendable plate to move into the open-ring position shown by FIG. 1. The laterally-directed compressive forces applied to the elongated, generally cylindrical ribs 52 and 54 of that bendable plate by the backing 24 will assure full movement of that bendable plate into the open-ring position shown by FIG. 1. That bendable plate will be kept from moving beyond the position shown 1 by FIG. 1 by the engagement of the portion 46 of reduced thickness with the enlarged heads 36 on the posts 34.

The unitary member which includes the backing 24 and the covers 20 and 22 and the portions 26 and 28 of reduced thickness will preferably be made from propylene; because propylene is extremely resistant to fatigue. Where that unitary member is made from propylene, the covers 20 and 22 can be opened and closed millions of time without any fatiguing of those covers or of the backing 24 or of the reduced thickness portions 26 and 28. The unitary member which includes the bendable plate 44 and the J-shaped projections 58 and 60 thereon also will preferably be made of propylene. Where that is done, the reduced thickness portion 46 can be flexed millions of times without any fatiguing thereof.

The bendable plate 44 is preferably made by the use of a mold which has a patrix 68 and a matrix 88. The

patrix 68 has two elongated semi-cylindrical recesses 70 and 72 therein; and the matrix 88 has two elongated recesses 9G and 92 which have the cross section of a quarter of a cylinder. An elongated rib 74 of frusto triangular cross section is formed on the upper surface of the patrix 63, and that rib is half-way between the: grooves 70 and 72. That rib will serve to define the lower portion of the section 46 of reduced cross sectionand the inclined surfaces 50 on the bendable plate 44. Openings 76 are provided in the patrix 68, and those openings are adjacent the opposite ends of that patrix; and each of the openings 76 has a cylindrical recess 77 adjacent the lower end thereof.

The numeral 78 denotes extensions on the patrix 68 which have vertical sides and arcuate tops. Grooves 8i and 82 of semi-circular cross section are provided in the vertically directed sides of the extensions 78 and in parts of the arcuate tops of those extensions. A projection 84 is provided on each of the extensions 7 8, and a notch 86 is provided in each of those extensions. The grooves 80 and 82 form the inner faces of the J-shaped projections 58 and 6t), and the projections 84 define the notches 62 in the projections 58 while the notches 86 define the extensions 64 on the projections 60.

The numeral 4 denotes a recess in the matrix 88 which defines the largest part of the bendable plate 44-; and that recess is contiguous with the elongated recesses 90 and 92. An elongated rib 96 extends into the recess 94; and that rib is frusto-triangular in cross section to define the surfaces 48 and the upper face of the portion 46 of reduced thickness. Grooves 98 and 100 of semi-circular cross section are formed in the matrix 88, and those grooves will be in register with the grooves 81 and 82 of semi-circular cross section in the extensions 78 on the patrix 68 of the mold. Sockets 97 are provided adjacent the opposite ends of the matrix 88, and those sockets are in register with the openings '76 in the patrix 68. The sockets 97 accommodate the upper ends of pins 102 which have the shanks thereof extending upwardly through the openings 76 in the patrix 68 and into those sockets. Enlarged bottoms on those pins are seated in the recesses 77 of the patrix 68.

When the patrix 68 and the matrix 88 are assembled together, they form a cavity that precisely defines the bendable plate 44. Specifically, the elongated grooves 70 and 90 define the elongated, generally cylindrical rib 52, the grooves 72 and 92 define the elongated, generally cylindrical rib 54, the recess 94 will coact with the ribs 74 and 96 to define the bendable plate 44 with its portion 46 of reduced thickness and the surfaces 50 and 43, the grooves 811 and 98 will define the J-shaped projections 58, the grooves 82 and 100 will define the J-shaped projections 60, the projections 84 will define the notches 62, the

notches 86 will define the extensions 64, the extensions 78 will define the openings 66, and the pins 102 will define the openings 56. Suitable gates will be provided for the mold, and they will conduct the fluid propylene into the cavity and enable it to form the unitary member which includes the bendable plate 44 and the J-shaped projections 58 and 60.

The L-shaped levers 40 will be suitably formed by appropriate metal-working equipment. Specifically, those levers will preferably be formed by punching them out of a plate or sheet of metal.

The unitary member which includes the backing 24, the covers 20 and 22, the reduced thickness portions 26 and 28, the concave recesses 30 and 32, and the posts 34 will preferably be formed in a mold which includes a matrix 1% and a patrix 111). That matrix has an elongated recess 1G8 therein and that recess has the curvature of the unstressed backing 24; and a gate 164 extends through the matrix 166 to the recess 1158. Elongated ribs 107 are provided on the matrix adjacent the recess 168; and those ribs will help define the reduced thickness portions 26 and 28 of the loose-leaf binder.

The patrix 110 has an elongated recess 112 therein; and

that recess is generally rectangular in cross section. A generally rectangular block 114 is disposed within the recess 112, and that block has two elongated passageways 115 extending vertically upwardly through it adjacent the ends thereof. The block 114 also has an elongated arcuate rib 116 adjacent the upper left-hand edge thereof and has an elongated arcuate rib 118 adjacent the upper righthand edge thereof. Grooves are provided in the block 114 immediately below the arcuate ribs 116 and 118 and a convex top surface is provided on the block 114 intermediate the ribs 116 and 118. That convex surface is complementary to the recess 108 in the matrix 106.

Two generally cylindrical sockets 120 are provided in the block 114, and those sockets will be in register with the passages in that block. Enlarged ends 122 are provided for the sockets and elongated pins 124 extend through the elongated passageways 115 in the patrix 110 and the block 114 and extend through the enlarged ends 122 into the sockets 120. Elongated ribs 126 are formed on the patrix 110 at points disposed outwardly of the recess 112; and wide fiat recesses 128 and 130 are formed in the patrix 110 at points disposed outwardly of the elongated ribs 126.

When the matrix and the patrix 110 are assembled together, they form a cavity which defines the unitary mem-' her which includes the backing 24, the front cover 20, rear cover 22, the reduced thickness portions 26 and 28, the concave recesses 30 and 32, the posts 34, the enlarged heads 36 on those posts, and recesses 38 in those posts. Specifically, the recess 128 will define the front cover 20, the recess 130 will define the back cover22, the ribs 107 and 126 will define the portions 26 and 28 of reduced thickness, the recess 108 and the top of the block 114 will define the backing 24, the ribs 116 and 118 will define the concave recesses 30 and 32, the cylindrical recesses 1211 will define the posts 34, the enlarged ends 122 of those recesses will define the enlarged heads 36, and the pins 124 will define the recesses 38 in the posts 34. In forming the unitary member which includes the covers 20 and 22, the backing24, the portions 26 and 28 of reduced thickness, the concave recesses 30 and 32, the posts 34, and the enlarged heads 36, propylene will beforced to pass through the gate 104 into the cavity defined by the patrix 110 and the matrix 106. Once that propylene has solidified, the matrix 106 can be separated from the patrix 11 3, and then the backing 24 can be stripped away from the patrix.

The covers and backing of the loose-leaf binder provided by the present invention can thus be formed by one simple molding operation, the bendable plate 44 of that loose-leaf binder can be formed by another simple mold ing operation, and the L-shaped levers 40 can be formed by a simple punching operation. As a result, the four components of the loose-leaf binder provided by the present invention can be made inexpensively and in quantity. Furthermore, once those four components have been formed, they can easily be assembled with a minimum of time and cost. As a result, the present invention provides an inexpensive but durable loose-leaf binder;

Whereas the drawing and accompanying description have shown and described a preferred embodiment of the present invention, it should be apparent to those skilled in the art that various changes may be made in the form of the invention without affecting the scope thereof.

What I claim is:

1'; A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, J-shaped ring-defining projections adjacent the opposite edges thereof, and levers that have openings therein and that can beused to force said J-shaped ring-defining projections apart, said second unitary member being elongated and being generally rectangular in plan and having said opposite edges thereof elongated, said second unitary member having an elongated portion of reduced cross section extending. longitudinally thereof and disposed intermediate said elongated opposite edges, said elongated portion'of reduced cross section having fiat upper and lower faces, said second unitary member having surfaces that incline outwardly and upwardly from said upper face of said elongated potrion of reduced cross section to the upper face of said second unitary member to define an elongated recess of frusto-triangular cross section, said second unitary member having surfaces that incline outwardly and downwardly from said lower face of said elongated portion of reduced cross section to the lower face of said second unitary member to define an elongated recess of frusto-triangular cross section, openings in said second unitary member adjacent the opposite ends of said second unitary member that extend through said elongated portion of reduced cross section and through said outwardly and upwardly inclined surfaces and through said outwardly and downwardly inclined surfaces, said second unitary member being formed of flexible material and being bendable about said elongated portion of reduced cross section to move the confronting ends of said J-shaped ring-defining projections toward or away from each other, the first said unitary member having elongated portions thereof which define elongated concave recesses that accommodate and confine the said elongated opposite edges of said second unitary member while permitting said elongated opposite edges of said second unitary member to move relative to said elongated concave recesses, said elongated opposite edges of said second unitary member being formed as ribs of arcuate cross section and with radii that are complementary to the radii of said concave recesses of the first said unitary member, the exposed surfaces of each of said elongated opposite edges defining three quadrants, the first said unitary member having pins adjacent the opposite ends thereof which have enlarged heads that are compressible because of recesses therein, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being larger in cross section than are said openings in said second unitary member and normally overlying said upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member having portions of reduced thickness intermediate said backing portion thereof and said front and rear covers thereof to serve as hinges for said front and rear covers thereof, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said back ing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other and will thereby urge said elongated portion of reduced cross section of said second unitary member either toward said backing portion of the first said unitary member or toward said enlarged heads of said pins, the confronting ends of said J-shaped projections on said second unitary member being spaced apart whenever said elongated portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

2. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections adjacent the opposite edges thereof, and levers that have openings therein and that can be used to force said ring-defining projections apart, said second unitary member being elongated and having said opposite edges thereof elon-' gated, said second unitary member having an elongated portion of reduced cross section extending longitudinally thereof and disposed intermediate said elongated opposite edges, said second unitary member having surfaces that incline outwardly and upwardly from the upper face of said elongated portion of reduced cross section to the upper face of said second unitary member to define an elongated recess, said second unitary member having surfaces that incline outwardly and downwardly from the lower face of said elongated portion of reduced cross section to the lower face of said second unitary member to define an elongated recess, openings in said second unitary member adjacent the opposite ends of said second unitary member that extend through said elongated por-'- tion of reduced cross section and through said outwardly and upwardly inclined surfaces and through said outwardly and downwardly inclined surfaces, said second unitary member being formed of flexible material and being bendable about said elongated portion of reduced cross section to move the confronting ends of said ringdefining projections toward or away from each other, the first said unitary member having elongated portions thereof which define elongated concave recesses that accommodate and confine the said elongated opposite edges of said second unitary member While permitting said elongated opposite edges of said second unitary member to move relative to said elongated concave recesses, said elongated opposite edges of said second unitary member being formed as ribs of arcuate cross section and with radii that are complementary to the radii of said concave recesses of the first said unitary member, the exposed surfaces of each of said elongated opposite edges defining three quadrants, the first said unitary member having pins adjacent the opposite ends thereof which have enlarged heads that are compressible, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being larger in cross section, than are said openings in said second unitary member and normally overlying said upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a dis tance away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member having portions of reduced thickness intermediate said backing portion thereof and said front and rear covers thereof to serve as hinges for said front and rear covers thereof, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said backing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other and will thereby urge said elongated portion of reduced cross section of said second unitary member either toward said backing portion of the first said unitary member or toward said enlarged heads of said pins, the confronting ends of said projections on said second unitary member being spaced apart whenever said elongated portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

3. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, and levers that have openings therein and that can be used to force said ring-defining projections apart, said second unitary member being elongated and having the opposite edges thereof elongated, said second unitary member having an elongated portion of reduced cross section extending longitudinally thereof and disposed intermediate said elongated opposite edges, openings in said second unitary member adjacent the opposite ends of said second unitary member that extend through said elongated portion of reduced cross section, said second unitary member being formed of flexible material and being bendable about said elongated portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accommodate and confine the said elongated opposite edges of said second unitary member while permitting said elongated opposite edges of said second unitary member to move relative to said recesses, said elongated opposite edges of said second unitary member being formed as ribs of arcuate cross section and with radii that are complementary to the radii of said recesses of the first said unitary member, the first said unitary member having pins adjacent the opposite ends thereof which have enlarged heads that are compressible, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being larger in cross section than are said openings in said second unitary member and normally overlying the upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said backing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other and will thereby urge said elongated portion of reduced cross section of said second unitary member either toward said backing portion of the first said unitary member or toward said enlarged heads of said pins, the confronting ends of said projections on said second unitary member being spaced apart whenever said elongated portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary v 10 member is adjacent said backing portion unitary member. p

4. A loose leaf binder that comprises a unitary'member which constitutes the backing and the front and'rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, and levers that have openings therein and that can be used to force said ring-defining projections apart, said second unitary member being elongated and having the opposite edges thereof elongated, said second unitary member having an elongated portion of reduced cross section extending longitudinally thereof and disposed intermediate said elongated opposite edges, said second unitary member having surfaces that incline outwardly and upwardly from the upper face of said elongated portion of reduced cross section to the upper face of said second unitary member to define an elongated recess, said second unitary member having surfaces that incline outwardly and downwardly from the lower face of said elongated portion of reduced cross section to the lower face of said second unitary member to define an elongated recess, openings in said second unitary member adjacent the opposite ends of said second unitary member that extend through said elongated portion of reduced cross section and through said outwardly and upwardly inclined surfaces and through said outwardly and downwardly inclined surfaces, said second unitary member being formed of flexible material and being bendable about said elongated portion of reduced cross section to move the confronting endsof said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accommodate and confine the said elongated opposite edges of said second unitary member while permitting said elongated opposite edges of said second unitary member to move relative to said recesses, said elongated opposite edges of said second unitary member being formed as ribs of arcuate cross section, the first said unitary member having pins adjacent the opposite ends thereof which have enlarged heads that are compressible, said pins being in register with and extending through said openings" in said second unitary member, said enlarged heads on said pins being larger in cross section than are said openmgs in said second unitary member and normally overlying the upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member having portions of reduced thickness intermediate said backing portion thereof and said front and rear covers thereof to serve as hinges forsaid front and rear covers thereof, the first saidunitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, the confronting ends of said projections on said second unitary member being spaced apart whenever said elongated por tion of reduced cross section of said second unitary member is adjacent said enlarged heads of said. pins and being in engagement whenever said elongated portion of re of the first said 1 l duced cross section of said second unitary member is adjacent said backing portion of the first said unitary member. a

5. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, and levers that have openings therein and that can be used to force said ring-defining projections apart, said second unitary member being elongated and having the opposite edges thereof elongated, said second unitary member having an elongated portion of reduced cross section extending longitudinally thereof and disposed intermediate said elongated opposite edges, openings in said second unitary member adjacent the opposite ends of said second unitary member that extend through said elongated portion of reduced cross section, said second unitary member being formed of flexible material and being bendable about said elongated portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accommodate and confine the said elongated opposite edges of said second unitary member while permitting said elongated opposite edges of said second unitary member to move relative to said recesses, the first said unitary member having pins adjacent the opposite ends thereof which have enlarged heads that are compressible, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being larger in cross section than are said openings in said second unitary member and normally overlying the upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, the confronting ends of said projections on said second unitary member being spaced apart whenever said elongated portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

6. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, and levers that have openings therein and that can be used to force said ring-defining projections apart, said second unitary member having a portion of reduced cross section extending longitudinally thereof and disposed intermedi ate the opposite edges thereof, openings in said second unitary member adjacent the opposite ends of said second unitary member, said second unitary member being formed of flexible material and being bendable about said portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accommo date and confine the opposite edges .of said second unitary member while permitting said opposite edges of said second unitary member to move relative to said recesses, said opposite edges of said second unitary member being formed as ribs, the first said unitary member having pins which have enlarged heads that are compressible, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being larger in cross section than are said openings in said second unitary member and normally overlying the upper face of said second unitary member to prevent accidental separation of said second unitary member from the first said unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance away fiom said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, said openings in said levers surrounding said pins, the opening-defining portions of said levers being disposed between said backing portion of the first said unitary member and said second unitary member, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said backing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other and will thereby urge said elongated portion of reduced cross sec tion of said second unitary member either toward said backing portion of the first said unitary member or toward said enlarged heads of said pins, the confronting ends of said projections on said second unitary member being spaced apart whenever said portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

7. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, said second unitary member having a portion of reduced cross section extending longitudinally thereof and disposed intermediate the opposite edges thereof, openings in said second unitary member adjacent the opposite ends of said second unitary member, said second unitary member being formed of flexible material and being bendable about said portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accornmodate and confine the opposite edges of said second unitary member while permitting said opposite edges of said second unitary member to move relative to said recesses, the first said unitary member having pins, said pins being 1n register with and extending through said openings in said second unitary member, said pins extending upwardly from the backing portion of the first said unitary member, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said backing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other, the confronting ends of said projections on said second unitary member being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

8. A loose leaf binder that comprises a unitary member which constitutes the backing and the front and rear covers for said binder, a second unitary member which has oppositely-directed, ring-defining projections thereon, said second unitary member having a portion of reduced cross section extending longitudinally thereof and disposed intermediate the opposite edges thereof, openings in said second unitary member, said second unitary member being formed of flexible material and being bendable about said portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses that accommodate and confine the opposite edges of said second unitary member while permitting said opposite edges of said second unitary member to move relative to said recesses, the first said unitary member having pins which have enlarged heads that are compressible, said pins being in register with and extending through said openings in said second unitary member, said enlarged heads on said pins being selectively compressible to a cross section that will enable them to pass through said openings in said second unitary member and thereby permit separation of said second unitary member from the first said unitary member, said pins extending upwardly from the backing portion of the first said unitary member and spacing said enlarged heads thereon a distance. away from said backing so said elongated portion of reduced cross section of said second unitary member can be moved toward and away from said backing portion of the first said unitary member, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the first said unitary member is less than the unstressed distance between said elongated edges of said second unitary member, whereby said backing portion of the first said unitary member will urge said elongated edges of said second unitary member toward each other, the confronting ends of said projections on said second unitary member being spaced apart whenever said portion of reduced cross section of said second unitary member is adjacent said enlarged heads of said pins and being in engagement whenever said elongated portion of reduced cross section of said second unitary member is adjacent said backing portion of the first said unitary member.

9. A loose leaf binder that comprises a first unitary member formed as a single molding of relatively stiff 14 plastic material which constitutes a backing and front and rear covers for said binder, said backing being elongated and being open to define an elongated open area of concave cross section, said covers comprising relatively rigid platesshaving an edge of each hinged to an elongated edge of said backing, the material between said backing and each of'said covers being of reduced cross section and being bendable about said material of reduced cross section to form said hinge for each of said covers, a second unitary member which is elongated and which has a plurality of oppositely-directed, ringdefining projections spaced along the length thereof, said second unitary member having a portion of reduced cross section extending longitudinally thereof and disposed intermediate the opposite elongated edges thereof, said second unitary member being bendable about said portion of reduced cross section to move the confronting ends of said ring-defining projections toward or away from each other, the first said unitary member having portions thereof which define recesses at the opposite edges of said open area defined by said backing that accommodate and confine the opposite edges of said second unitary member whenever said second unitary member is disposed within said open area defined by said backing, said second unitary member substantially closing said open area defined by said backing, said elongated recess-defining portions of the first said unitary member permitting said opposite edges of said second unitary member to move relative to said recesses, the first said unitary member being formed of resilient material and being formed so the unstressed distance between said recess-defining elongated portions of the backing is less than the unbent distance between said elongated edges of said second unitary member, whereby said backing of the first said unitary member will urge said elongated edges of said second unitary member toward each other and thereby bias said ring-defining projections away from each other whenever those ring-defining projections are in their open positions and will also bias said ring-defining projections toward each other whenever those ring-defining projections are in their closed position, the first said unitary member being formed of plastic material so said backing is yieldable but can respond to increases in the distance between said elongated recess-defining portions of the first said unitary member to urge said elongated edges of said second unitary member toward each other even more strongly.

References Cited in the file of this patent UNITED STATES PATENTS Stinson Feb. 6, 1962 

7. A LOOSE LEAF BINDER THAT COMPRISES A UNITARY MEMBER WHICH CONSTITUTES THE BACKING AND THE FRONT AND REAR COVERS FOR SAID BINDER, A SECOND UNITARY MEMBER WHICH HAS OPPOSITELY-DIRECTED, RING-DEFINING PROJECTIONS THEREON, SAID SECOND UNITARY MEMBER HAVING A PORTION OF REDUCED CROSS SECTION EXTENDING LONGITUDINALLY THEREOF AND DISPOSED INTERMEDIATE THE OPPOSITE EDGES THEREOF, OPENINGS IN SAID SAID SECOND UNITARY MEMBER, SAID SECOND UNITARY MEMBER SAID SECOND UNITARY MEMBER, SAID SECOND UNITARY MEMBER BEING FORMED OF FLEXIBLE MATERIAL AND BEING BENDABLE ABOUT SAID PORTION OF REDUCED CROSS SECTION TO MOVE THE CONFRONTING ENDS OF SAID RING-DEFINING PROJECTIONS TOWARD OR AWAY FROM EACH OTHER, THE FIRST SAID UNITARY MEMBER HAVING PORTIONS THEREOF WHICH DEFINE RECESSES THAT ACCOMMODATE AND CONFINE THE OPPOSITE EDGES OF SAID SECOND UNITARY MEMBER WHILE PERMITTING SAID OPPOSITE EDGES OF SAID SECOND UNITARY MEMBER TO MOVE RELATIVE TO SAID RECESSES, THE FIRST SAID UNITARY MEMBER HAVING PINS, SAID PINS BEING IN REGISTER WITH AND EXTENDING THROUGH SAID OPENINGS IN SAID SECOND UNITARY MEMBER, SAID PINS EXTENDING UPWARDLY FROM THE BACKING PORTION OF THE FIRST SAID UNITARY MEMBER, THE FIRST SAID UNITARY MEMBER BEING FORMED OF RESILIENT MATERIAL AND BEING FORMED SO THE UNSTRESSED DISTANCE BETWEEN SAID RECESS-DEFINING ELONGATED PORTIONS OF THE FIRST SAID UNITARY MEMBER IS LESS THAN THE UNSTRESSED DISTANCE BETWEEN SAID ELONGATED EDGES OF SAID SECOND UNITARY MEMBER, WHEREBY SAID BACKING PORTION OF THE FIRST SAID UNITARY MEMBER WILL URGE SAID ELONGATED EDGES OF SAID SECOND UNITARY MEMBER TOWARD EACH OTHER, THE CONFRONTING ENDS OF SAID PROJECTIONS ON SAID SECOND UNITARY MEMBER BEING IN ENGAGEMENT WHENEVER SAID ELONGATED PORTION OF REDUCED CROSS SECTION OF SAID SECOND UNITARY MEMBER IS ADJACENT SAID BACKING PORTION OF THE FIRST SAID UNITARY MEMBER. 